Fukushima Forgotten. Submitted by: Chris Rouse New Clear Free Solutions

Transcription

1 Fukushima Forgotten New Clear Free Solutions Comments on: CNSC Study of Consequences of a Hypothetical Severe Nuclear Accident and Effectiveness of Mitigation Measures Submitted by: Chris Rouse New Clear Free Solutions

2 TABLE OF CONTENTS 1.0 OVERVIEW COMMENTS Source Term Early Release Hydrogen Explosions Lake Ontario Consequences Economic Consequences Land Contamination Consequences CONCLUSION August

3 1.0 OVERVIEW As a frequent intervener in nuclear regulatory matters New Clear Free Solutions has doubts that CNSC staff will properly disposition comments received on this study so these comments are directed to the Commissioners. For over 50 years, the Canadian Public has been concerned with the safety of nuclear facilities, and what would be the consequences of a severe nuclear accident. At the Darlington hearings, the commissioners finally granted the public the right to know what the possible consequences of a severe nuclear accident are. We are concerned that this report has failed to objectively inform the public of the consequences of such an event. It is New Clear Free Solutions opinion that senior CNSC management have demonstrated that they have very little concern for safety. The report is not what the public wanted, not what the commission asked for, and fails to meet the objectives of the Nuclear Safety and Control Act. We ask that the report be redone with proper concern for safety taken into account. It is evident from this report that serious changes need to be made at the Canadian Nuclear Safety Commission. These changes need to start at the top with a total restructuring of senior CNSC management. These changes are needed so that concern for nuclear safety takes priority and not a back seat to CNSC concerns and opinions that the document would be used malevolently in a public hearing. It s a no-win proposition, whatever, whatever we think the Commission requested 1 New Clear Free Solutions is very concerned with the above quote from senior CNSC management and the subsequent size reduction of the source term to be much smaller than August

4 originally considered. It gives the impression of a real or apparent conflict of interest in the selection of the source term. As well, it gives the appearance of a deliberate attempt to misinform the commission on their request for information. These are violations of the CNSC values and ethics code, and those involved in the reduction of the original source term of the study should be investigated. New Clear Free Solutions has provided comments on the draft report to ensure proper concern for safety is taken in the final report. To be concerned with safety, the definition must be understood, and is as follows: Safety In the Fundamental Safety Principles (Safety Fundamentals), the generalized usage in this particular text of the term safety (i.e. to mean protection and safety) is explained as follows (Ref. [22], paras 3.1 and 3.2): 3.1. For the purposes of this publication, safety means the protection of people and the environment against radiation risks, and the safety of facilities and activities that give rise to radiation risks. Safety as used here and in the IAEA safety standards includes the safety of nuclear installations, radiation safety, the safety of radioactive waste management and safety in the transport of radioactive material; it does not include non-radiation-related aspects of safety Safety is concerned with both radiation risks under normal circumstances and radiation risks as a consequence of incidents 4, as well as with other possible direct consequences of a loss of control over a nuclear reactor core, nuclear chain reaction, radioactive source or any other source of radiation. Safety measures include actions to prevent incidents and arrangements put in place to mitigate their consequences if they were to occur. 4 Incidents includes initiating events, accident precursors, near misses, accidents and unauthorized acts (including malicious and non-malicious acts). The relevant part of the definition for these comments is that safety is concerned with the consequences of accidents. This is an extremely important aspect to the concept of nuclear safety, and is the fundamental flaw of this report and why it has failed to meet public expectations. The inclusion of accidents is meant to protect the public from the misuse of probabilities in determining the consequences of accidents. Once an accident does happen it should no longer be considered not credible and concern about the consequences of a similar accident becomes legitimized and required. Regretfully, it took an external event- common cause failure, multi-unit accident- for this type of scenario to be considered credible. Under the concept of nuclear safety, the industry can no longer hide behind faulty rational and questionable probabilities of the consequences of a Fukushima type event as not credible. This report failed to address the public s safety concerns with the consequences of an accident like the Fukushima accident, and has been done as if Fukushima was forgotten and the definition of safety was not understood. 3 August

5 2.0 COMMENTS 2.1 Source Term At a minimum the source term from the ongoing Fukushima accident should be included in the report as a sensitivity case. Choosing a source term of 100 Tb C-137, the minimum considered to be a large release, is not acceptable to the public. The generic large release (GLR) of C-134, used in this report, is 1843 times less than Chernobyl and 562 times less than Fukushima. Those involved in the selection of the GLR and the use of the three bear s paradigm should be investigated for possible breaches of the CNSC values and ethics code. The GLR used in this draft report is the same source term used for the Darlington New Build EA and site preparation licence hearings. This was deemed not acceptable in the courts after a judicial review of the EA and site preparation licence. The decision states 2 : [331] This seems to engage the realm of highly improbable, but possibility catastrophic, events. On policy grounds, it is logical that such scenarios should be considered by political decision-makers, because once again they seem to engage mainly questions of society s chosen level of protection against risk that will be difficult for a specialized regulator to assess with legitimacy. On this view, having found that such an analysis was required, it would seem more appropriate for the August

6 Panel to have insisted it be completed within the EA process, so that it could be considered in the s.37 context. If 100Tb of C-137 GLR is unfit for the courts, this regurgitated and less thorough report should also be considered unfit for its purpose as well. Notice the decision notes the difficulty the regulator might have in assessing a severe accident with legitimacy. This report shows that the CNSC could not overcome that difficultly, and independent experts should be commissioned to finalize the draft report based on feedback from the public. The final scope of the study should be determined through a round of public consultations, which should have happened in the first place. The revised final report could then be used to remedy the lack of such a study for the Darlington new build. 2.2 Early Release At a minimum, the timing and magnitudes of releases from the ongoing Fukushima accident should be used for this study. Early releases should not be excluded from this study as early release accidents have happened, and they are not physically impossible for a Candu reactor and as such need to be included in this study. 5 August

7 As seen in the INPO slide above TEPCO unsuccessfully tried to vent large releases long before 24 hours. As well from the slide it is evident that early releases had already began and hampered mitigation measures long before 24 hours. A Candu reactor that succumbs to an unmitigated total loss of heat sinks, like the Fukushima accident, can begin melting down within 4 to 5 hours 3. If the pressure tubes fail, first radiation is released directly into containment. In a mulit-unit accident, containment is unlikely to contain releases for 24 hours. If the steam generators fail first due to lack of adequate pressure relief 4, large releases can occur through a containment bypass as early as 4 to 5 hours into the accident. Large releases would even preclude core meltdown. 5 The Darlington refurbishment will replace the pressure tubes with new ones, but there is no plan to replace the steam generators. A combination of new pressure tubes and aged steam generators may lead to the early containment bypass scenario PLGS Response to CNSC Fukushima Task Force 4 E-DOCS-# CMD 13-M30.2 Submission from Sunil Nijhawan on the 2012 NPP Report 5 Modified Screen Shot from CNSC Video Understanding Nuclear Power Plants: Total Station Blackout 6 August

8 The public has been assured by the industry that the big lesson learned from Fukushima was expect the unexpected. Not including early releases is ignoring the expected and not acceptable. 2.3 Hydrogen Explosions At a minimum the study should include multiple sudden large radioactive dispersions by hydrogen explosions similar to the ongoing Fukushima accident. Planned hydrogen/deuterium mitigation measures are not adequate for an accident similar to Fukushima, and a similar explosion could occur at Darlington as stated in the CNSC Fukushima Task force report 6 : The rate of generation of combustible gas is beyond the capability of passive autocatalytic recombiners, and hydrogen explosions cannot be precluded. There are currently no plans to install PARS in the irradiated fuel bays or in the nonnuclear side of the reactors. Leakage from the containment into these areas may well cause a hydrogen explosion similar to the Unit 4 hydrogen explosion at Fukushima. The Unit 4 explosion was caused by the migration of hydrogen generated from the meltdown at Unit 3. 6 CNSC Fukushima Task Force Report 7 August

9 2.4 Lake Ontario Consequences At a minimum, the study should include all of the consequences of sustained releases to Lake Ontario like the ongoing Fukushima accident has into the Pacific Ocean. Source terms similar to that of the ongoing Fukushima accident should be used to determine the consequences. Although Lake Ontario is a large body of water, it pales in comparison to the Pacific, and similar releases would have a far greater effect on Lake Ontario. The study should also include any mitigation measures that may be planned if there are any. It is New Clear Free Solutions opinion that Canada and the US should procure technology that can filter radioactive water. This technology should be available so that it could be deployed in a timely manner to anywhere within North America as an important lesson learned in the mitigation from a Fukushima type accident. 8 August

10 2.5 Economic Consequences At a minimum the economic consequences of a Fukushima type accident should be included in the study. The study should include any mitigation measures such as the process and criteria for economic compensation, or planned increases to acceptable dose levels ect. One of the biggest consequences of a large nuclear accident is the economic impacts. This has been totally forgotten in this report, which is unacceptable. 9 August

11 2.6 Land Contamination Consequences At a minimum, the study should include potential radioactive fallout maps. Experience from the Fukushima accident shows that the land contamination generally stemmed from wet deposition from rain 7. The study should include sensitivity analysis on varying wind and rain patterns including the most probable weather patterns to a realistic worst case. Potential land contamination and relocation has severe societal consequences and needs to be addressed in the final report August

12 3.0 CONCLUSION This draft report does not meet the public expectations, and needs significant work to be deemed acceptable. The scope of the report needs to be clarified by a round of public consultations with due concern for safety. The consultations and final report should be completed by independent experts from outside of the CNSC. It is also New Clear Free Solutions recommendation that the CNSC office of Audit and Ethics review those responsible for the selection of the GLR for possible values and ethics code violations. 11 August